When a caller makes a telephone call to a telephone number that is shared by multiple members of a telephone service subscriber, that call is often answered by a member (the answering member) who is not the caller's desired or intended member (the intended member). This situation often occurs in, for example, a college dormitory room occupied by two or more students, a household of multiple members, an apartment shared by several roommates, and other similar dwelling units.
When the answering member finds out that he or she is not the person desired by the caller, he or she may offer to do one of several things for the caller. For example, if the intended member is unavailable, the answering member may offer to take a message from the caller. If the intended member is available, the answering member may ask the caller to wait while he or she passes the telephone handset to the intended member.
In a situation in which the intended member is not available, although the answering member may offer to take a message, that offer is not always acceptable to the caller for various reasons. For example, the caller is often put on hold or interrupted numerous times before the answering member successfully finds a piece of paper and a writing instrument. Furthermore, even if the caller leaves a message with the answering member, that message does not always reach the intended member successfully. For example, the piece of paper with the written message may be subsequently misplaced or the message may be incorrectly recorded by the answering member.
In a situation in which the intended member is available, it may be inconvenient for the answering member to get the intended member's attention. For example, if a father (the answering member) on the second floor bedroom answers a call for his son (the intended member) who is practicing drums in the basement, the father would have to go down two flights of stairs to get the son's attention.
In another situation in which the caller wishes to transmit a document to the subscriber who uses the same telephone line for both voice and data communication, the caller has to call a second time if the first call was answered by a person instead of a fax machine.